KKXX and for some proteins XKXX is a target peptide motif located in the C terminus in the amino acid structure of a protein responsible for retrieval of endoplasmic reticulum (ER) membrane proteins to and from the Golgi apparatus. These ER membrane proteins are transmembrane proteins that are then embedded into the ER membrane after transport from the Golgi.[1] This motif is exclusively cytoplasmic[2] and interacts with the COPI protein complex to target the ER from the cis end of the Golgi apparatus by retrograde transport.[3]

The abbreviation KKXX is formed by the corresponding standard abbreviations for lysine (K) and any amino acid (X). This letter system was defined by the IUPAC and IUBMB in 1983, and is as follows:

See also

References

  1. ^ Martin J. Vincent; Annelet S. Martin; Richard W. Compans (January 9, 1998). "Function of the KKXX Motif in Endoplasmic Reticulum Retrieval of a Transmembrane Protein Depends on the Length and Structure of the Cytoplasmic Domain". The Journal of Biological Chemistry. 273 (2): 950–956. doi:10.1074/jbc.273.2.950. PMID 9422755.
  2. ^ Erin C. Gaynor; Stephan te Heesen; Todd R. Graham; Markus Aebi; Scott D. Emr (November 1, 1994). "Signal-mediated Retrieval of a Membrane Protein from the Golgi to the ER in Yeast". The Journal of Cell Biology. 127 (3): 653–665. doi:10.1083/jcb.127.3.653. PMC 2120234. PMID 7962050.
  3. ^ Mariano Stornaiuolo; Lavinia V. Lotti; Nica Borgese; Maria-Rosaria Torrisi; Giovanna Mottola; Gianluca Martire; Stefano Bonatti (March 2003). "KDEL and KKXX Retrieval Signals Appended to the Same Reporter Protein Determine Different Trafficking between Endoplasmic Reticulum, Intermediate Compartment, and Golgi Complex". Molecular Biology of the Cell. 14 (3): 889–902. doi:10.1091/mbc.E02-08-0468. PMC 151567. PMID 12631711.


Categories